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Tim White

By TIME StaffThursday, Apr. 01, 2010

Courtesy of Tim White

Age: 60
Occupation: Paleontologist
Previous TIME 100 Appearances: 0

White and a team of fellow paleontologists discovered the oldest fossil skeleton of a human ancestor, which has been named Ardi, thought to have walked the earth 4.4 million years ago. That's more than a million years before Lucy, who was previously thought to be the earliest hominid skeleton. According to White, his team's discovery is the "closest we have ever been able to come" to finding the missing-link common ancestor between humans and chimps.